Hi fellas,

I have a 2011 GMC Sierra 5.3 which has been turned to a forged 383 stroker. My current setup is in the sig, 94mm turbo which is not making good power. I am making 550 wheel horsepower at 15 psi and it is lifting the heads a bit. So, can't go any higher. I am not making full use of the turbo. I know the 94mm turbo was a mistake.

I am looking to size down. What size turbo would you go for on a 383 stroker?
I am looking to be around 900 - 1000 wheel horsepower

Thanks!

 

A borg S480 could do it.

 

Yea that 94mm is way too big. A good 80-85mm would be a good fit.

 

Thanks for the reply.

To be more realistic my goals are to be 800+ wheel horsepower.

As for the S480 there is a T4 and a T6 version. Which one would be more suitable for me? Also, what A/R would you go with?

 

You could realistically use either, but whatever matches your current hot side would be easiest. The T6 will be cheaper and have more top end, but the T4 will probably spool better.

 

Thanks for the detailed response. That makes sense. I was looking at Precision's 7675 CEA and was set on that.

Do you think that would've been good as well?

 

Not sure the turbine side on the 7675 is big enough for 383 cubes.....The Borg Warner S476 or S480 with the 92mm or 96mm turbine will likely do it.

 

I was going to say the same... an s480 would behave a heck of a lot better and reach your power goals, both present and future.

 

The majority seem to be recommending the BW S480. Looks great! I need input on whether the T4 or T6 would the a better option.
Also the A/R sizes available are:
-1.15
-1.32
-1.45
-1.58

I need your opinions as I do not want to make the same expensive mistake!

Thanks guys

 

Go for a T6 1.32. Good new is exhaust housings are relatively cheap.